Opel Frontera UE. Manual - part 124

5A–42

BRAKE CONTROL SYSTEM

Chart B-8 2WD Controller in 4WD Vehicle Controller (DTC 13 (Flash out) /  C0285 (Serial 
communications)), 4WD State Input Signal Failure (DTC 24 (Flash out) / C0282 (Serial 
communications))

Chart B-9 Pump Motor Failure (DTC 32 (Flash out) / C0267, C0268 (Serial communications))

Step

Action

Yes

No

1 

Remove coil integrated module connector.
Is the coil integrated module connector (C-4) terminal 8 line 
normally?

Go to Step 2

Repair.

Go to Step 3 

2 

Is the 4WD controller normally?

Replace EHCU.

Go to Step 3 

Replace 4WD 

controller.

Go to Step 3 

3 

1. Reconnect all components, ensure all components are 

properly mounted.

2. Clear diagnostic trouble code.

Was this step finished?

Repeat the “Basic  

diagnostic flow 

chart"

Go to Step 3

Step

Action

Yes

No

1 

1. Turn the key off.

2. Disconnect coil integrated module connector.

3. Measure the voltage between terminal 1 of the coil integrated 

module connector (C-5) and body ground.

Is the voltage equal to the battery voltage?

Go to Step 2

Repair fuse/

harness 

between battery 

and coil 

integrated 

module 

connector (C-5) 

terminal 1.

Go to Step 5

2 

Is the harness from the hydraulic unit connected to the coil 
integrated module connector?

Go to Step 3

Connect to the 

connector.

Go to Step 3

3 

Is the harness from the hydraulic unit normally?

Go to Step 4

Replace EHCU.

Go to Step 5

4 

Is the check resistance of hydraulic unit connector terminals 1 
and 2 between 0.2 and 1.0 ohms?

Replace EHCU.

Go to Step 5

Replace EHCU.

Go to Step 5

5 

1. Reconnect all components, ensure all components are 

properly mounted.

2. Clear diagnostic trouble code.

Was this step finished?

Repeat the “Basic  

diagnostic flow 

chart"

Go to Step 5

BRAKE CONTROL SYSTEM

5A–43

Chart B-10 EHCU Valve Relay Failure (DTC 35 (Flash out) / C0265, C0266 (Serial 
communications))

Chart B-11 FL Isolation Solenoid Coil Failure (DTC 41 (Flash out) / C0245, C0247 (Serial 
communications))

Chart B-12 FL Dump Solenoid Coil Failure (DTC 42 (Flash out) / C0246, C0248 (Serial 
communications))

Step

Action

Yes

No

1 

1. Turn the key off.

2. Disconnect coil integrated module connector.

3. Measure the voltage between terminal 1 of the coil integrated 

module connector (C-5) and body ground.

Is the voltage equal to the battery voltage?

Replace EHCU.

Go to Step 2

Repair fuse and 

harness coil 

integrated 

module 

connector (C-5) 

terminal 1 and 

battery.

Go to Step 2

2 

1. Reconnect all components, ensure all components are 

properly mounted.

2. Clear diagnostic trouble code.

Was this step finished?

Repeat the “Basic  

diagnostic flow 

chart"

Go to Step 2

Step

Action

Yes

No

1 

Was the “EHCU Connector Pin–out Checks" performed?

Go to Step 2

Go to “EHCU 

Connector Pin–out 

Checks."

2 

1. Turn the key switch to off.

2. Disconnect the 2–way EHCU connector (C–5) from the 

EHCU.

3. Inspect the connector for damage or corrosion.

Is the connector free from damage or corrosion?

Go to Step 3

Repair the 

connector. Repeat 

the “Basic 

Diagnostic Flow 

Chart."

3 

1. Replace the Coil Integrated Module.

2. Reconnect all component, ensure all components are 

properly mounted.

Was this step finished?

Repeat the “Basic  

diagnostic flow 

chart" 

Go to Step 3

Step

Action

Yes

No

1 

Was the “EHCU Connector Pin–out Checks" performed?

Go to Step 2

Go to “EHCU 

Connector Pin–out 

Checks."

2 

1. Turn the key switch to off.

2. Disconnect the 2–way EHCU connector (C–5) from the 

EHCU.

3. Inspect the connector for damage or corrosion.

Is the connector free from damage or corrosion?

Go to Step 3

Repair the 

connector. Repeat 

the “Basic 

Diagnostic Flow 

Chart."

3 

1. Replace the Coil Integrated Module.

2. Reconnect all component, ensure all components are 

properly mounted.

Was this step finished?

Repeat the “Basic  

diagnostic flow 

chart" 

Go to Step 3

5A–44

BRAKE CONTROL SYSTEM

Chart B-13 FR Isolation Solenoid Coil Failure (DTC 43 (Flash out) / C0241, C0243 (Serial 
communications))

Chart B-14 FR Dump Solenoid Coil Failure (DTC 44(Flash out) / C0242, C0244 (Serial 
communications))

Chart B-15 Rear Isolation Solenoid Coil Failure (DTC 45 (Flash out) / C0251, C0253 (Serial 
communications))

Step

Action

Yes

No

1 

Was the “EHCU Connector Pin–out Checks" performed?

Go to Step 2

Go to “EHCU 

Connector Pin–out 

Checks."

2 

1. Turn the key switch to off.

2. Disconnect the 2–way EHCU connector (C–5) from the 

EHCU.

3. Inspect the connector for damage or corrosion.

Is the connector free from damage or corrosion?

Go to Step 3

Repair the 

connector. Repeat 

the “Basic 

Diagnostic Flow 

Chart."

3 

1. Replace the Coil Integrated Module.

2. Reconnect all component, ensure all components are 

properly mounted.

Was this step finished?

Repeat the “Basic  

diagnostic flow 

chart" 

Go to Step 3

Step

Action

Yes

No

1 

Was the “EHCU Connector Pin–out Checks" performed?

Go to Step 2

Go to “EHCU 

Connector Pin–out 

Checks."

2 

1. Turn the key switch to off.

2. Disconnect the 2–way EHCU connector (C–5) from the 

EHCU.

3. Inspect the connector for damage or corrosion.

Is the connector free from damage or corrosion?

Go to Step 3

Repair the 

connector. Repeat 

the “Basic 

Diagnostic Flow 

Chart."

3 

1. Replace the Coil Integrated Module.

2. Reconnect all component, ensure all components are 

properly mounted.

Was this step finished?

Repeat the “Basic  

diagnostic flow 

chart" 

Go to Step 3

Step

Action

Yes

No

1 

Was the “EHCU Connector Pin–out Checks" performed?

Go to Step 2

Go to “EHCU 

Connector Pin–out 

Checks."

2 

1. Turn the key switch to off.

2. Disconnect the 2–way EHCU connector (C–5) from the 

EHCU.

3. Inspect the connector for damage or corrosion.

Is the connector free from damage or corrosion?

Go to Step 3

Repair the 

connector. Repeat 

the “Basic 

Diagnostic Flow 

Chart."

3 

1. Replace the Coil Integrated Module.

2. Reconnect all component, ensure all components are 

properly mounted.

Was this step finished?

Repeat the “Basic  

diagnostic flow 

chart" 

Go to Step 3

BRAKE CONTROL SYSTEM

5A–45

Chart B-16 Rear Dump Solenoid Coil Failure (DTC 46 (Flash out) / C0252, C0254 (Serial 
communications))

Chart B-17 FL Speed Sensor Open or Shorted (DTC 51 (Flash out) / C0225 (Serial 
communications))

Step

Action

Yes

No

1 

Was the “EHCU Connector Pin–out Checks" performed?

Go to Step 2

Go to “EHCU 

Connector Pin–out 

Checks."

2 

1. Turn the key switch to off.

2. Disconnect the 2–way EHCU connector (C–5) from the 

EHCU.

3. Inspect the connector for damage or corrosion.

Is the connector free from damage or corrosion?

Go to Step 3

Repair the 

connector. Repeat 

the “Basic 

Diagnostic Flow 

Chart."

3 

1. Replace the Coil Integrated Module.

2. Reconnect all component, ensure all components are 

properly mounted.

Was this step finished?

Repeat the “Basic  

diagnostic flow 

chart" 

Go to Step 3

Step

Action

Yes

No

1 

1. Turn the key off.

2. Disconnect coil integrated module connector.

3. Measure the resistance between coil integrated module 

connector (C-4) terminals 2 and 10.

Is the resistance between 2.0k and 2.8k ohms?

Check for faults 

in harness 

between speed 
sensor and coil 

integrated 

module.

Fault found:  

Repair, and 

perform system 

self-check.

No fault found: 

Replace coil 

integrated 

module.

Go to Step 3

Go to Step 2

2 

Measure the FL speed sensor resistance at the sensor 
connector.
Is the resistance between 2.0k and 2.8k ohms?

Repair harness 

abnormality 

between 

sensors and 

coil integrated 

module.

Go to Step 3

Replace sensor.

Go to Step 3

3 

1. Reconnect all components, ensure all components are 

properly mounted.

2. Clear diagnostic trouble code.

Was this step finished?

Repeat the “Basic  

diagnostic flow 

chart" 

Go to Step 3